Systems for displaying images

ABSTRACT

A system for displaying images is provided. The system includes a capacitive touch sensor device includes a dielectric layer having a sensing area and covered by a transparent substrate. A plurality of series of first sense electrodes and a plurality of series of second sense electrodes are embedded in a first level of the dielectric layer and within the sensing area. Each series of first sense electrodes extends along a first direction and each series of second sense electrodes extends along a second direction substantially different from the first direction. A plurality of signal lines are embedded in a second level lower than the first level of the dielectric layer and extends along the second direction. Each signal line is correspondingly and electrically connected to one of the plurality of series of first sense electrodes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a touch panel display technology, and inparticular to a capacitive touch sensor device for a touch paneldisplay.

2. Description of the Related Art

A touch sensor device is typically integrated with a flat panel displaydevice (such as an LCD, AMOLED or the like) to form a touch paneldisplay. Touch panel displays are typically mounted on electronicdevices, such as portable personal computers, personal digitalassistants (PDAs), electronic books, projectors, mobile phones, and thelike. The touch panel display is capable of conducting input functionsby a finger, a stylus, a pen, or the like. Generally, touch paneldisplays are divided into resistive type, capacitive type, acoustic wavetype, and optical type touch panel displays according to the sensingmethod applied, in which the capacitive touch panel display has gainedan increasing amount of attention and popularity because it has goodtouch sensitivity and structural stability.

FIG. 1 illustrates a plan view of an arrangement of sense electrodes fora conventional capacitive touch sensor device. The capacitive touchsensor device 100 typically includes a plurality of series of senseelectrodes 101 and a plurality of series of sense electrodes 103underlying the plurality of series of sense electrodes 101, in whicheach series of sense electrodes 101 is perpendicular to each series ofsense electrodes 103 as viewed from a top-view perspective. Each seriesof sense electrodes 101 is connected to a connection line 101 a and eachseries of sense electrodes 103 is connected to a connection line 103 a.The connections lines 101 a and 103 a are disposed on a border regionthat is typically on two orthogonal sides of the sensor device 100, suchthat the series of sense electrodes 101 can be electrically connected toexternal circuits (not shown) by the connections lines 101 a and 103 a.

For some touch panel displays, particularly those applied in mobiledevices, such as mobile phones and PDAs, it is desirable to minimize thewidth of the border region around the display to reduce dimensionsthereof. The connection lines in the border region, however, aretypically disposed on two orthogonal sides of the touch panel display,which fixes the width of the border region, making reduction of thedimensions of the border region very difficult.

Accordingly, there exists a need in the art for development of a touchsensor device, capable of reducing the width of the border region.

BRIEF SUMMARY OF THE INVENTION

A detailed description is given in the following embodiments withreference to the accompanying drawings. Systems for displaying imagesare provided. An exemplary embodiment of a system for displaying imagescomprises a capacitive touch sensor device comprising a dielectric layerhaving a sensing area and covered by a transparent substrate. Aplurality of series of first sense electrodes and a plurality of seriesof second sense electrodes are embedded in a first level of thedielectric layer and within the sensing area. Each series of first senseelectrodes extends along a first direction and each series of secondsense electrodes extends along a second direction substantiallydifferent from the first direction. A plurality of signal lines areembedded in a second level lower than the first level of the dielectriclayer and extends along the second direction. Each signal line iscorrespondingly and electrically connected to one of the plurality ofseries of first sense electrodes.

BRIEF DESCRIPTION OF DRAWINGS

The invention can be more fully understood by reading the subsequentdetailed description and examples with references made to theaccompanying drawings, wherein:

FIG. 1 is a plan view of an arrangement of sense electrodes for aconventional capacitive touch sensor device;

FIG. 2A is a plan view of an embodiment of a system for displayingimages including a capacitive touch sensor device according to theinvention;

FIG. 2B is a cross section along 2B-2B′ line shown in FIG. 2A;

FIG. 3 is a plan view of another embodiment of a system for displayingimages including a capacitive touch sensor device according to theinvention;

FIG. 4 is a plan view of yet another embodiment of a system fordisplaying images including a capacitive touch sensor device accordingto the invention; and

FIG. 5 schematically shows another embodiment of a system for displayingimages.

DETAILED DESCRIPTION OF INVENTION

The following description is of the best-contemplated mode of carryingout the invention. This description is provided for the purpose ofillustrating the general principles of the invention and should not betaken in a limiting sense. The scope of the invention is best determinedby reference to the appended claims.

Systems for displaying images are provided. Referring to FIGS. 2A and2B, in which FIG. 2A is a plan view of an embodiment of a system fordisplaying images including a capacitive touch sensor device 200according to the invention and FIG. 2B is the cross section along 2B-2B′line shown in FIG. 2A. In the embodiment, the capacitive touch sensordevice 200 comprises a transparent substrate 201, a dielectric layer203, a plurality of series of first sense electrodes 204, a plurality ofseries of second sense electrodes 202, and a plurality of signal lines206. The transparent substrate 201 is directly touched by an inputmeans, such as a finger, a stylus, a pen, or the like. The transparentsubstrate 201 may be comprised of glass, quartz, or other flexible orinflexible polymer transparent materials.

The dielectric layer 203 (shown in FIG. 2B) is covered by thetransparent substrate 201 and has a sense area 203 a (shown in FIG. 2A)for disposing sense electrodes. In the embodiment, the dielectric layer203 may comprise a single layer, such as a silicon oxide layer, siliconnitride layer or other transparent insulating polymer layer, or multiplelayers, such as stacked silicon oxide layers, silicon nitride layers,other transparent insulating polymer layers, or combination thereof.

The plurality of series of first sense electrodes 204 and the pluralityof series of second sense electrodes 202 are embedded in a first levelof the dielectric layer 203 and within the sensing area 203 a. In theembodiment, each series of first sense electrodes 204 extends along afirst direction and each series of second sense electrodes 202 extendsalong a second direction different from the first direction. Forexample, the first direction is parallel to a horizontal direction withrespect to FIG. 2A, and the second direction is parallel to a verticaldirection with respect to FIG. 2A, such that each series of first senseelectrodes 204 is substantially perpendicular to each series of secondsense electrodes 202. In some embodiments, the second direction may notbe perpendicular to the first direction. In the embodiment, each seriesof first sense electrodes 204 and each series of second sense electrodes202 may be formed by patterning the same transparent conductive layer,such as an indium tin oxide (ITO) or indium zinc oxide (IZO) layer usinglithography and etching processes. Moreover, two adjacent secondelectrodes 202 in the same series of second sense electrodes 202 areconnected to each other by a connection portion 202 a that is embeddedin the first level of the dielectric layer 203 and is formed of the sametransparent conductive layer as the series of second sense electrodes202. Two adjacent first electrodes 204 in the same series of first senseelectrodes 204 are connected to each other by two interconnects (e.g.conductive plugs/vias) 204 a and one connection portion 204 c, whereinthe connection portion 204 c is embedded in a second level lower thanthe first level of the dielectric layer 203 and the interconnects 204 aare disposed between the first and second level of the dielectric layer203 for electrically connecting the corresponding connection portion 204c. Note that two interconnects 204 a are disposed under each first senseelectrode 204. In order to simplify and clearly exhibit the diagram,only some interconnects 204 a are depicted. In one embodiment, theconnection portion 204 c is formed of a transparent conductive layer(such as an ITO or IZO layer) which is different from the layer used forformation of the series of first sense electrodes 204.

The plurality of signal lines 206 are embedded in the second level ofthe dielectric layer 203 and extend along the second direction. In oneembodiment, the plurality of signal lines 206 and the connectionportions 204 c may be formed by patterning the same transparentconductive layer, such as an ITO or IZO layer using lithography andetching processes. In the embodiment, the plurality of signal lines 206and the plurality of series of second sense electrodes 202 arealternately arranged as viewed from a top-view perspective, such thatonly one signal line 206 is disposed between the adjacent series ofsecond sense electrodes 202. As a result, the signal lines 206 can beuniformly arranged over the sensing area 203 a; thereby minimizing thevisibility of the signal lines 206. In the case where one signal line206 is disposed between the adjacent series of second sense electrodes202, the number of the plurality of series of first sense electrodes 204may be one less than that of the plurality of series of second senseelectrodes 202. Alternatively, the number of the plurality of series offirst sense electrodes 204 may be one more than or equal to that of theplurality of series of second sense electrodes 202.

Each signal line 206 is correspondingly and electrically connected toone of the plurality of series of first sense electrodes 204. Forexample, each signal line 206 passes under one first sense electrode 204in each series of first electrodes 204. Moreover, each signal line 206is electrically connected to the corresponding series of first senseelectrodes 204 by an interconnect (e.g. a conductive plug/via) 204 b.These interconnects 204 b may be visible and make errors in thecapacitance measurements if they are clustered together or arranged in aline. In one embodiment, the interconnects 204 b for each signal line206 and the corresponding series of first sense electrodes 204 are notarranged in a line and are distributed over the sensing area 203 a asviewed from a top-view perspective to minimize the visibility of theinterconnects 204 b and prevent errors in capacitance measurements.

A common electrode layer 208 is embedded in a third level lower than thesecond level of the dielectric layer 203 and corresponds to the sensingarea 203 a. Namely, the common electrode layer 208 substantiallyoverlaps the entire sensing area 203 a. In one embodiment, the commonelectrode layer 208 may be formed of a transparent conductive layer(such as an ITO or IZO layer) different from that for formation of thefirst and second sense electrodes 204 and 202 and the signal lines 206.In the embodiment, the common electrode layer 208 and/or the pluralityof first sense electrodes 204 may be electrically connected to a groundor a low impedance electrode. As a result, the presence of the inputmeans, such as a finger, a stylus, a pen, or the like, above the signalline(s) 206 has little effect on the capacitance associated with thesignal line(s) 206, and the capacitances between the plurality of thesignal lines 206 and the plurality of series of second sense electrodes202 can be reduced. Note that changes in these capacitances may produceerrors in the output of the touch sensor device 200.

A plurality of first connection lines 206 a corresponds to the pluralityof signal lines 206 and a plurality of second connection lines 202 bcorresponds to the plurality of series of second sense electrodes 202.In the embodiment, each first connection line 206 a extends from thecorresponding signal line 206 to the outside of the sensing area 203 afor electrically connecting the corresponding series of first senseelectrode 204 to external circuits (not shown). Moreover, each secondconnection line 202 b extends from the corresponding series of secondsense electrodes 202 to the outside of the sensing area 203 a forelectrically connecting the corresponding series of second senseelectrode 202 to external circuits (not shown). In one embodiment, thefirst connection lines 206 a may be formed of the same transparentconductive layer as that for formation of the signal line 206. Also, thesecond connection line 202 b may be formed of the same transparentconductive layer as that for formation of the second sense electrode202. In the embodiment, the plurality of first connection lines 206 aand the plurality of second connection lines 202 b are located at thesame side of the sensing area 203. According to the foregoingembodiments, since the connection lines for electrically connecting thesense electrodes to external circuits can be arranged at the same sideof the sense area of the touch sensor device, the width of the borderregion around the touch panel display can be reduced, and thus thedimensions of a touch panel display can also be reduced.

Referring to FIGS. 3 and 4, which illustrate various embodiments of asystem for displaying images including a capacitive touch sensor deviceaccording to the invention. Elements in FIGS. 3 and 4 that are the sameas those in FIGS. 2A to 2B are labeled with the same reference numbersas in FIGS. 2A to 2B and are not described again for brevity. In theembodiment shown in FIG. 2A, the touch sensor device 200 has an aspectratio of 1:1, and thus the pitch P1 of the adjacent series of firstsense electrodes 204 is equal to the pitch P2 of the adjacent series ofsecond sense electrodes 202. In the embodiments shown in FIG. 3 or 4,the touch sensor device 200 may not have an aspect ratio equal to 1:1,and thus the pitch P1 of the adjacent series of first sense electrodes204 is different from the pitch P2 of the adjacent series of secondsense electrodes 202. For example, in the embodiments shown in FIG. 3 or4, the touch sensor device 200 may have an aspect ratio of 4:3 or 16:9,and thus the pitch P1 may be greater than the pitch P2. Additionally,although the plurality of first connection lines 206 a and the pluralityof second connection lines 202 b are located at the same side of thesensing area 203 in the embodiment shown in FIG. 2A, the plurality offirst connection lines 206 a and the plurality of second connectionlines 202 b may be located at opposing sides of the sensing area 203,respectively, as shown in FIG. 4. In the embodiment shown in FIG. 4,since the connection lines for electrically connecting the senseelectrodes to external circuits can be arranged at opposing sides,rather than orthogonal sides of the sense area of the touch sensordevice, the width of the border region around a touch panel display usedin portrait mode can be reduced, and thus the dimension of a touch paneldisplay application is also reduced.

FIG. 5 schematically shows another embodiment of a system for displayingimages which, in this case, is implemented as a touch panel display 300or an electronic device 500 such as a projector, an electronic book, alaptop computer, a mobile phone, a digital camera, a personal digitalassistant (PDA), a desktop computer, a television, a car display or aportable DVD player. The described touch sensor device 200 can beincorporated into the touch panel display 300. In some embodiments, thetouch sensor device 200 can be incorporated into the electronic device500. As shown in FIG. 5, the electronic device 500 comprises the touchpanel display 300 and an input unit 400. Moreover, the input unit 400 iscoupled to the touch panel display 300 and is operative to provide inputsignals (e.g. image signals) to the touch panel display 300 to generateimages.

While the invention has been described by way of example and in terms ofpreferred embodiment, it is to be understood that the invention is notlimited thereto. To the contrary, it is intended to cover variousmodifications and similar arrangements (as would be apparent to thoseskilled in the art). Therefore, the scope of the appended claims shouldbe accorded the broadest interpretation so as to encompass all suchmodifications and similar arrangements.

1. A system for displaying images, comprising: a capacitive touch sensordevice, comprising: a dielectric layer having a sensing area and coveredby a transparent substrate; a plurality of series of first senseelectrodes and a plurality of series of second sense electrodes embeddedin a first level of the dielectric layer and within the sensing area,wherein each series of first sense electrodes extends along a firstdirection and each series of second sense electrodes extends along asecond direction substantially different from the first direction; and aplurality of signal lines embedded in a second level lower than thefirst level of the dielectric layer and extending along the seconddirection, wherein each signal line is correspondingly and electricallyconnected to one of the plurality of series of first sense electrodes.2. The system of claim 1, further comprising a plurality of firstconnection lines corresponding to the plurality of signal lines and aplurality of second connection lines corresponding to the plurality ofseries of second sense electrodes, wherein each first connection lineextends from the corresponding signal line to the outside of the sensingarea, and each second connection line extends from the correspondingseries of second sense electrodes to the outside of the sensing area. 3.The system of claim 2, wherein the pluralities of first and secondconnection lines are located at the same side of the sensing area. 4.The system of claim 2, wherein the pluralities of first and secondconnection lines are located at opposing sides of the sensing area,respectively.
 5. The system of claim 1, further comprising a commonelectrode layer embedded in a third level lower than the second level ofthe dielectric layer and corresponding to the sensing area.
 6. Thesystem of claim 5, wherein the common electrode layer is formed of aconductive transparent layer.
 7. The system of claim 5, wherein thecommon electrode layer is electrically connected to a ground or a lowimpedance electrode.
 8. The system of claim 1, wherein the plurality ofseries of first sense electrodes and the plurality of series of secondsense electrodes are formed of the same conductive transparent layer. 9.The system of claim 1, wherein the plurality of signal lines is formedof a conductive transparent layer.
 10. The system of claim 1, whereineach first sense electrode in each series of first sense electrodes areelectrically connected together and each second sense electrode in eachseries of second sense electrodes are electrically connected together.11. The system of claim 1, wherein each signal line passes under onefirst sense electrode in each series of first sense electrodes.
 12. Thesystem of claim 1, wherein each series of first sense electrodes areelectrically connected to a ground or a low impedance electrode.
 13. Thesystem of claim 1, wherein each signal line is correspondingly andelectrically connected to one of the plurality of series of first senseelectrodes by an interconnect, wherein the interconnects for each signalline and the corresponding series of first sense electrodes are notarranged in a line as viewed from a top-view perspective.
 14. The systemof claim 1, wherein the plurality of signal lines and the plurality ofseries of second sense electrodes are alternately arranged.
 15. Thesystem of claim 14, wherein the number of the plurality of series offirst sense electrodes is one more than that of the plurality of seriesof second sense electrodes.
 16. The system of claim 14, wherein thenumber of the plurality of series of first sense electrodes is one lessthan that of the plurality of series of second sense electrodes.
 17. Thesystem of claim 14, wherein the number of the plurality of series offirst sense electrodes is equal to that of the plurality of series ofsecond sense electrodes.
 18. The system as claimed in claim 1, furthercomprising: a touch panel display comprising the capacitive touch sensordevice; and an input unit coupled to the touch panel display andoperative to provide input signals to the touch panel display, such thatthe touch panel display displays images.
 19. The system of claim 18,wherein the system comprises an electronic device comprising the touchpanel display.
 20. The system of claim 19, wherein the electronic deviceis a projector, an electronic book, a laptop computer, a mobile phone, adigital camera, a personal digital assistant, a desktop computer, atelevision, a car display or a portable DVD player.